Question

ex: carbon has how many valence electrons? ex: chlorine has how many valence electrons?

Explanation:

Step1: Determine electron configuration

Carbon has atomic number 6. Its electron configuration is \(1s^{2}2s^{2}2p^{2}\). The valence shell is the second shell (\(n = 2\)). The number of electrons in the valence shell (\(2s^{2}+2p^{2}\)) is \(4\).

Step2: Determine electron configuration for chlorine

Chlorine has atomic number 17. Its electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{5}\). The valence shell is the third shell (\(n = 3\)). The number of electrons in the valence shell (\(3s^{2}+3p^{5}\)) is \(7\).

Answer:

Carbon has \(4\) valence electrons. Chlorine has \(7\) valence electrons.